Administrative Considerations for Oracle Publishers
After an Oracle Publisher is configured and the replication change tracking mechanisms are in place, administrators of the Oracle database system can still use standard Oracle database utilities and perform typical system administration tasks. However, you should be aware of the effects on the published data of performing certain administrative tasks.
With the exception of dropping or modifying a column that is published for replication, or dropping or modifying any replication objects, these considerations do not apply to snapshot publications.
Importing and loading data
Triggers are used in change tracking for transactional publications on Oracle. Changes to published tables can be replicated to Subscribers only if the replication triggers fire when an update, insert, or delete occurs. The Oracle utilities Oracle Import and SQL*Loader both have options that affect whether triggers will fire when rows are inserted into replicated tables with these utilities.
With Oracle Import, you can set the option ignore to 'y' or 'n' (the default is 'n'). If ignore is set to 'n', the table is dropped and re-created during import. This removes replication triggers and disables replication. If ignore is set to 'y', import will attempt to load the rows into the existing table, which fires the replication triggers. Therefore, ensure ignore is set to 'y' when importing into a replicated table with the Import tool.
With SQL*Loader, you can set the option direct to 'true' or 'false' (the default is 'false'). If direct is set to 'false', rows are inserted using conventional INSERT statements, which fire replication triggers. If direct is set to 'true', the load is optimized, and triggers are not fired. Therefore, ensure direct is set to 'false' when loading into a replicated table with the SQL*Loader tool.
Making changes to published objects
The following actions require no special considerations:
Rebuilding indexes on published tables.
Adding user triggers to a published table.
The following action requires you to stop all activity on the published tables:
- Moving a published table.
The following actions require you to drop the publication, perform the operation, and then recreate the publication:
Truncating a published table.
Renaming a published table.
Adding a column to a published table.
Dropping or modifying a column that is published for replication.
Performing non-logged operations.
Dropping or modifying replication objects
You must drop and reconfigure the Publisher if you drop or modify any Publisher level tracking tables, triggers, sequences, or stored procedures. For a partial list of these objects, see Objects Created on the Oracle Publisher.
For information about dropping and reconfiguring the Publisher, see the section "Changes are made that require reconfiguration of the Publisher" in the topic Troubleshooting Oracle Publishers.